Pivoting anvil for surgical circular stapler

ABSTRACT

A circular stapler apparatus for stapling tissue has a circular stapling head operable to drive staples toward an anvil to form the staples in a circular array. The anvil includes an anvil head, a proximal shaft extending proximally from the anvil head and having a proximal end disposed in a first plane, and a first pivot connecting the anvil head to the proximal shaft. The first pivot is operable to be disposed in a second plane that is laterally offset from the first plane. The anvil is configured to rotate via movement through multiple pivot points. The anvil may be configured to rotate to a position in which a portion of the anvil head is disposed below the first pivot and between the first pivot and the proximal shaft such that the anvil head is acutely angled with respect to a longitudinal axis of the proximal shaft.

BACKGROUND

In some settings, a surgeon may want to position a surgical instrumentthrough an orifice of the patient and use the instrument to adjust,position, attach, and/or otherwise interact with tissue within thepatient. For instance, in some surgical procedures, portions of thegastrointestinal tract may be cut and removed to eliminate undesirabletissue or for other reasons. Once the desired tissue is removed, theremaining portions may need to be recoupled together. One such tool foraccomplishing these anastomotic procedures is a circular stapler that isinserted through a patient's orifice.

Examples of circular surgical staplers are described in U.S. Pat. No.5,205,459, entitled “Surgical Anastomosis Stapling Instrument,” issuedApr. 27, 1993; U.S. Pat. No. 5,271,544, entitled “Surgical AnastomosisStapling Instrument,” issued Dec. 21, 1993; U.S. Pat. No. 5,275,322,entitled “Surgical Anastomosis Stapling Instrument,” issued Jan. 4,1994; U.S. Pat. No. 5,285,945, entitled “Surgical Anastomosis StaplingInstrument,” issued Feb. 15, 1994; U.S. Pat. No. 5,292,053, entitled“Surgical Anastomosis Stapling Instrument,” issued Mar. 8, 1994; U.S.Pat. No. 5,333,773, entitled “Surgical Anastomosis Stapling Instrument,”issued Aug. 2, 1994; U.S. Pat. No. 5,350,104, entitled “SurgicalAnastomosis Stapling Instrument,” issued Sep. 27, 1994; and U.S. Pat.No. 5,533,661, entitled “Surgical Anastomosis Stapling Instrument,”issued Jul. 9, 1996. The disclosure of each of the above-cited U.S.patents is incorporated by reference herein. Some such staplers areoperable to clamp down on layers of tissue, cut through the clampedlayers of tissue, and drive staples through the layers of tissue tosubstantially seal the severed layers of tissue together near thesevered ends of the tissue layers, thereby joining two severed ends ofan anatomical lumen.

Merely additional other exemplary surgical staplers are disclosed inU.S. Pat. No. 4,805,823, entitled “Pocket Configuration for InternalOrgan Staplers,” issued Feb. 21, 1989; U.S. Pat. No. 5,415,334, entitled“Surgical Stapler and Staple Cartridge,” issued May 16, 1995; U.S. Pat.No. 5,465,895, entitled “Surgical Stapler Instrument,” issued Nov. 14,1995; U.S. Pat. No. 5,597,107, entitled “Surgical Stapler Instrument,”issued Jan. 28, 1997; U.S. Pat. No. 5,632,432, entitled “SurgicalInstrument,” issued May 27, 1997; U.S. Pat. No. 5,673,840, entitled“Surgical Instrument,” issued Oct. 7, 1997; U.S. Pat. No. 5,704,534,entitled “Articulation Assembly for Surgical Instruments,” issued Jan.6, 1998; U.S. Pat. No. 5,814,055, entitled “Surgical ClampingMechanism,” issued Sep. 29, 1998; U.S. Pat. No. 6,978,921, entitled“Surgical Stapling Instrument Incorporating an E-Beam Firing Mechanism,”issued Dec. 27, 2005; U.S. Pat. No. 7,000,818, entitled “SurgicalStapling Instrument Having Separate Distinct Closing and FiringSystems,” issued Feb. 21, 2006; U.S. Pat. No. 7,143,923, entitled“Surgical Stapling Instrument Having a Firing Lockout for an UnclosedAnvil,” issued Dec. 5, 2006; U.S. Pat. No. 7,303,108, entitled “SurgicalStapling Instrument Incorporating a Multi-Stroke Firing Mechanism with aFlexible Rack,” issued Dec. 4, 2007; U.S. Pat. No. 7,367,485, entitled“Surgical Stapling Instrument Incorporating a Multistroke FiringMechanism Having a Rotary Transmission,” issued May 6, 2008; U.S. Pat.No. 7,380,695, entitled “Surgical Stapling Instrument Having a SingleLockout Mechanism for Prevention of Firing,” issued Jun. 3, 2008; U.S.Pat. No. 7,380,696, entitled “Articulating Surgical Stapling InstrumentIncorporating a Two-Piece E-Beam Firing Mechanism,” issued Jun. 3, 2008;U.S. Pat. No. 7,404,508, entitled “Surgical Stapling and CuttingDevice,” issued Jul. 29, 2008; U.S. Pat. No. 7,434,715, entitled“Surgical Stapling Instrument Having Multistroke Firing with OpeningLockout,” issued Oct. 14, 2008; and U.S. Pat. No. 7,721,930, entitled“Disposable Cartridge with Adhesive for Use with a Stapling Device,”issued May 25, 2010. The disclosure of each of the above-cited U.S.patents is incorporated by reference herein. While the surgical staplersreferred to above are described as being used in endoscopic procedures,it should be understood that such surgical staplers may also be used inopen procedures and/or other non-endoscopic procedures.

While various kinds of surgical stapling instruments and associatedcomponents have been made and used, it is believed that no one prior tothe inventor(s) has made or used the invention described in the appendedclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims which particularly pointout and distinctly claim this technology, it is believed this technologywill be better understood from the following description of certainexamples taken in conjunction with the accompanying drawings, in whichlike reference numerals identify the same elements and in which:

FIG. 1 depicts a side elevation view of an exemplary circular staplingsurgical instrument;

FIG. 2A depicts an enlarged longitudinal cross-section view of anexemplary stapling head assembly of the instrument of FIG. 1 showing anexemplary anvil in an open position;

FIG. 2B depicts an enlarged longitudinal cross-sectional view of thestapling head assembly of FIG. 2A showing the anvil in a closedposition;

FIG. 2C depicts an enlarged longitudinal cross-sectional view of thestapling head assembly of FIG. 2A showing an exemplary staple driver andblade in a fired position;

FIG. 3 depicts an enlarged partial cross-sectional view of an exemplarystaple formed against the anvil;

FIG. 4A depicts an enlarged side elevation view of an exemplary actuatorhandle assembly of the surgical instrument of FIG. 1 with a portion ofthe body removed, showing a trigger in an unfired position and a lockoutfeature in a locked position;

FIG. 4B depicts an enlarged side elevation view of the actuator handleassembly of FIG. 4A, showing the trigger in a fired position and thelockout feature in an unlocked position;

FIG. 5 depicts an enlarged partial perspective view of an exemplaryindicator assembly of the surgical instrument of FIG. 1 showing anindicator window and indicator lever;

FIG. 6 depicts an diagrammatic view of the indicator window of FIG. 5showing an exemplary indicator bar and exemplary corresponding staplerepresentations;

FIG. 7A depicts a partial, cross-sectional perspective view of anexemplary anvil in a first position in which the anvil has interactedwith a stapling head assembly to create an anastomosis;

FIG. 7B depicts a partial, cross-sectional perspective view of the anvilof FIG. 7A in a second position in which an anvil head of the anvil hasbeen tilted away from a link and an anvil shaft portion;

FIG. 7C depicts a partial, cross-sectional perspective view of the anvilof FIG. 7A in a third position in which a link of the anvil shaft istilted away from the anvil shaft portion;

FIG. 8 depicts a partial cross-sectional, perspective view of anotherexemplary anvil in a first position in which the anvil has interactedwith a stapling head assembly to create an anastomosis; and

FIG. 9 depicts a partial cross-sectional, perspective view of the anvilof FIG. 8 in a second position in which an anvil head is tilted about anoff-center pivot of an anvil shaft portion of the anvil.

The drawings are not intended to be limiting in any way, and it iscontemplated that various embodiments of the technology may be carriedout in a variety of other ways, including those not necessarily depictedin the drawings. The accompanying drawings incorporated in and forming apart of the specification illustrate several aspects of the presenttechnology, and together with the description serve to explain theprinciples of the technology; it being understood, however, that thistechnology is not limited to the precise arrangements shown.

DETAILED DESCRIPTION

The following description of certain examples of the technology shouldnot be used to limit its scope. Other examples, features, aspects,embodiments, and advantages of the technology will become apparent tothose skilled in the art from the following description, which is by wayof illustration, one of the best modes contemplated for carrying out thetechnology. As will be realized, the technology described herein iscapable of other different and obvious aspects, all without departingfrom the technology. Accordingly, the drawings and descriptions shouldbe regarded as illustrative in nature and not restrictive.

I. Overview of Exemplary Circular Stapling Surgical Instrument

FIGS. 1-6 depict an exemplary circular surgical stapling instrument (10)having a stapling head assembly (20), a shaft assembly (60), and anactuator handle assembly (70), each of which will be described in moredetail below. Shaft assembly (60) extends distally from actuator handleassembly (70) and stapling head assembly (20) is coupled to a distal endof shaft assembly (60). In brief, actuator handle assembly (70) isoperable to actuate a staple driver (24) of stapling head assembly (20)to drive a plurality of staples (66) out of stapling head assembly (20).Staples (66) are bent to form completed staples by an anvil (40) that isattached at the distal end of instrument (10). Accordingly, tissue (2),shown in FIGS. 2A-2C, may be stapled utilizing instrument (10).

In the present example, instrument (10) comprises a closure system and afiring system. The closure system comprises a trocar (38), a trocaractuator (39), and a rotating knob (98). An anvil (40) may be coupled toa distal end of trocar (38). Rotating knob (98) is operable tolongitudinally translate trocar (38) relative to stapling head assembly(20), thereby translating anvil (40) when anvil (40) is coupled totrocar (38), to clamp tissue between anvil (40) and stapling headassembly (20). The firing system comprises a trigger (74), a triggeractuation assembly (84), a driver actuator (64), and a staple driver(24). Staple driver (24) includes a knife (36) configured to severtissue when staple driver (24) is actuated longitudinally. In addition,staples (66) are positioned distal to a plurality of staple drivingmembers (30) of staple driver (24) such that staple driver (24) alsodrives staples (66) distally when staple driver (24) is actuatedlongitudinally. Thus, when trigger (74) is actuated and triggeractuation assembly (84) actuates staple driver (24) via driver actuator(64), knife (36) and members (30) substantially simultaneously severtissue (2) and drive staples (66) distally relative to stapling headassembly (20) into tissue. The components and functionalities of theclosure system and firing system will now be described in greaterdetail.

A. Exemplary Anvil

As shown in FIGS. 1-2C, anvil (40) is selectively coupleable toinstrument (10) to provide a surface against which staples (66) may bebent to staple material contained between stapling head assembly (20)and anvil (40). Anvil (40) of the present example is selectivelycoupleable to a trocar or pointed rod (38) that extends distallyrelative to stapling head assembly (20). Referring to FIGS. 2A-2C, anvil(40) is selectively coupleable via the coupling of a proximal shaft (42)of anvil (40) to a distal tip of trocar (38). Anvil (40) comprises agenerally circular anvil head (48) and a proximal shaft (42) extendingproximally from anvil head (48). In the example shown, proximal shaft(42) comprises a tubular member (44) having resiliently biased retainingclips (46) to selectively couple anvil (40) to trocar (38), though thisis merely optional, and it should be understood that other retentionfeatures for coupling anvil (40) to trocar (38) may be used as well. Forexample, C-clips, clamps, threading, pins, adhesives, etc. may beemployed to couple anvil (40) to trocar (38). In addition, while anvil(40) is described as selectively coupleable to trocar (38), in someversions proximal shaft (42) may include a one-way coupling feature suchthat anvil (40) cannot be removed from trocar (38) once anvil (40) isattached. Merely exemplary one-way features include barbs, one waysnaps, collets, collars, tabs, bands, etc. Of course still otherconfigurations for coupling anvil (40) to trocar (38) will be apparentto one of ordinary skill in the art in view of the teachings herein. Forinstance, trocar (38) may instead be a hollow shaft and proximal shaft(42) may comprise a sharpened rod that is insertable into the hollowshaft.

Anvil head (48) of the present example comprises a plurality of stapleforming pockets (52) formed in a proximal face (50) of anvil head (48).Accordingly, when anvil (40) is in the closed position and staples (66)are driven out of stapling head assembly (20) into staple formingpockets (52), as shown in FIG. 2C, legs (68) of staples (66) are bent toform completed staples. It should be understood that staple formingpockets (52) are merely optional and may be omitted in some versions.

With anvil (40) as a separate component, it should be understood thatanvil (40) may be inserted and secured to a portion of tissue (2) priorto being coupled to stapling head assembly (20). By way of example only,anvil (40) may be inserted into and secured to a first tubular portionof tissue (2) while instrument (10) is inserted into and secured to asecond tubular portion of tissue (2). For instance, the first tubularportion of tissue (2) may be sutured to or about a portion of anvil(40), and the second tubular portion of tissue (2) may be sutured to orabout trocar (38).

As shown in FIG. 2A, anvil (40) is then coupled to trocar (38). Trocar(38) of the present example is shown in a distal most actuated position.Such an extended position for trocar (38) may provide a larger area towhich tissue (2) may be coupled prior to attachment of anvil (40). Inaddition, the extended position of trocar (38) may also provide foreasier attachment of anvil (40) to trocar (38). Trocar (38) furtherincludes a tapered distal tip. Such a tip may be capable of piercingthrough tissue and/or aiding the insertion of anvil (40) on to trocar(38), though the tapered distal tip is merely optional. For instance, inother versions trocar (38) may have a blunt tip. In addition, or in thealternative, trocar (38) may include a magnetic portion (not shown)which may attract anvil (40) towards trocar (38). Of course stillfurther configurations and arrangements for anvil (40) and trocar (38)will be apparent to one of ordinary skill in the art in view of theteachings herein.

When anvil (40) is coupled to trocar (38), the distance between aproximal face of the anvil (40) and a distal face of stapling headassembly (20) defines a gap distance d. Trocar (38) of the presentexample is translatable longitudinally relative to stapling headassembly (20) via an adjusting knob (98) located at a proximal end ofactuator handle assembly (70), as will be described in greater detailbelow. Accordingly, when anvil (40) is coupled to trocar (38), rotationof adjusting knob (98) enlarges or reduces gap distance d by actuatinganvil (40) relative to stapling head assembly (20). For instance, asshown sequentially in FIGS. 2A-2B, anvil (40) is shown actuatingproximally relative to actuator handle assembly (70) from an initial,open position to a closed position, thereby reducing the gap distance dand the distance between the two portions of tissue (2) to be joined.Once the gap distance d is brought within a predetermined range,stapling head assembly (20) may be fired, as shown in FIG. 2C, to stapleand sever tissue (2) between anvil (40) and stapling head assembly (20).Stapling head assembly (20) is operable to staple and sever tissue (2)by a user pivoting a trigger (74) of actuator handle assembly (70), aswill be described in greater detail below.

As noted above, gap distance d corresponds to the distance between anvil(40) and stapling head assembly (20). When instrument (10) is insertedinto a patient, this gap distance d may not be easily viewable.Accordingly, a moveable indicator bar (110), shown in FIGS. 5-6, isprovided to be visible through an indicator window (120) positionedopposite to trigger (74). Indicator bar (110) is operable to move inresponse to rotation of adjusting knob (98) such that the position ofindicator bar (110) is representative of the gap distance d. As shown inFIG. 6, indicator window (120) further comprises a scale (130) whichindicates that the anvil gap is within a desired operating range (e.g.,a green colored region or “green zone”) and a corresponding staplecompression representation at each end of scale (130). By way of exampleonly, as shown in FIG. 6, a first staple image (132) depicts a largestaple height while a second staple image (134) depicts a small stapleheight. Accordingly, a user can view the position of the coupled anvil(40) relative to the stapling head assembly (20) via indicator bar (110)and scale (130). The user may then adjust the positioning of anvil (40)via adjusting knob (98) accordingly.

Referring back to FIGS. 2A-2C, a user sutures a portion of tissue (2)about tubular member (44) such that anvil head (48) is located within aportion of the tissue (2) to be stapled. When tissue (2) is attached toanvil (40), retaining clips (46) and a portion of tubular member (44)protrude out from tissue (2) such that the user may couple anvil (40) totrocar (38). With tissue (2) coupled to trocar (38) and/or anotherportion of stapling head assembly (20), the user attaches anvil (40) totrocar (38) and actuates anvil (40) proximally towards stapling headassembly (20) to reduce the gap distance d. Once instrument (10) iswithin the operating range, the user then staples together the ends oftissue (2), thereby forming a substantially contiguous tubular portionof tissue (2).

Anvil (40) may be further constructed in accordance with at least someof the teachings of U.S. Pat. No. 5,205,459; U.S. Pat. No. 5,271,544;U.S. Pat. No. 5,275,322; U.S. Pat. No. 5,285,945; U.S. Pat. No.5,292,053; U.S. Pat. No. 5,333,773; U.S. Pat. No. 5,350,104; U.S. Pat.No. 5,533,661, the disclosures of which are incorporated by referenceherein; and/or in accordance with other configurations as will beapparent to one of ordinary skill in the art in view of the teachingsherein.

B. Exemplary Stapling Head Assembly

Stapling head assembly (20) of the present example is coupled to adistal end of shaft assembly (60) and comprises a tubular casing (22)housing a slidable staple driver (24) and a plurality of staples (66)contained within staple pockets (32). Staples (66) and staple pockets(32) are disposed in a circular array about tubular casing (22). In thepresent example, staples (66) and staple pockets (32) are disposed in apair of concentric annular rows of staples (66) and staple pockets (32).Staple driver (24) is operable to actuate longitudinally within tubularcasing (22) in response to rotation of trigger (74) of actuator handleassembly (70). As shown in FIGS. 2A-2C, staple driver (24) comprises aflared cylindrical member having a trocar opening (26), a central recess(28), and a plurality of members (30) disposed circumferentially aboutcentral recess (28) and extending distally relative to shaft assembly(60). Each member (30) is configured to contact and engage acorresponding staple (66) of the plurality of staples (66) within staplepockets (32). Accordingly, when staple driver (24) is actuated distallyrelative to actuator handle assembly (70), each member (30) drives acorresponding staple (66) out of its staple pocket (32) through a stapleaperture (34) formed in a distal end of tubular casing (22). Becauseeach member (30) extends from staple driver (24), the plurality ofstaples (66) are driven out of stapling head assembly (20) atsubstantially the same time. When anvil (40) is in the closed position,staples (66) are driven into staple forming pockets (52) to bend legs(68) of the staples (66), thereby stapling the material located betweenanvil (40) and stapling head assembly (20). FIG. 3 depicts one merelyexemplary staple (66) driven by a member (30) into a staple formingpocket (32) of anvil (40) to bend legs (68).

Staple driver (24) further includes a cylindrical knife (36) that iscoaxial to trocar opening (26) and inset from staple pockets (32). Inthe present example, cylindrical knife (36) is disposed within centralrecess (28) to translate distally with staple driver (24). When anvil(40) is secured to trocar (38), as described above, anvil head (48)provides a surface against which cylindrical knife (36) cuts thematerial contained between anvil (40) and stapling head assembly (20).In some versions, anvil head (48) may include a recess (not shown) forcylindrical knife (36) to aid in cutting the material (e.g., byproviding a cooperative shearing edge). In addition, or in thealternative, anvil head (48) may include one or more opposingcylindrical knives (not shown) offset from cylindrical knife (36) suchthat a scissor-type cutting action may be provided. Still otherconfigurations will be apparent to one of ordinary skill in the art inview of the teachings herein. Stapling head assembly (20) is thusoperable to both staple and cut tissue (2) substantially simultaneouslyin response to actuation by actuator handle assembly (70).

Of course stapling head assembly (20) may be further constructed inaccordance with at least some of the teachings of U.S. Pat. No.5,205,459; U.S. Pat. No. 5,271,544; U.S. Pat. No. 5,275,322; U.S. Pat.No. 5,285,945; U.S. Pat. No. 5,292,053; U.S. Pat. No. 5,333,773; U.S.Pat. No. 5,350,104; U.S. Pat. No. 5,533,661, the disclosures of whichare incorporated by reference herein; and/or in accordance with otherconfigurations as will be apparent to one of ordinary skill in the artin view of the teachings herein.

As noted previously, staple driver (24) includes a trocar opening (26).Trocar opening (26) is configured to permit trocar (38) tolongitudinally slide relative to stapling head assembly (20) and/orshaft assembly (60). As shown in FIGS. 2A-2C, trocar (38) is coupled toa trocar actuator (39) such that trocar (38) can be actuatedlongitudinally via rotation of rotating knob (98), as will be describedin greater detail below in reference to actuator handle assembly (70).In the present example, trocar actuator (39) comprises an elongated,relatively stiff shaft coupled to trocar (38), though this is merelyoptional. In some versions, actuator (39) may comprise a longitudinallystiff material while permitting lateral bending such that portions ofinstrument (10) may be selectively bent or curved during use; orinstrument (10) may include a preset bent shaft assembly (60). Onemerely exemplary material is nitinol. When anvil (40) is coupled totrocar (38), trocar (38) and anvil (40) are translatable via actuator(39) to adjust the gap distance d between anvil (40) and stapling headassembly (20). Still further configurations for actuator (39) tolongitudinally actuate trocar (38) will be apparent to one of ordinaryskill in the art in view of the teachings herein.

C. Exemplary Shaft Assembly

Stapling head assembly (20) and trocar (38) are positioned at a distalend of shaft assembly (60), as shown in FIGS. 2A-2C. Shaft assembly (60)of the present example comprises an outer tubular member (62) and adriver actuator (64). Outer tubular member (62) is coupled to tubularcasing (22) of stapling head assembly (20) and to a body (72) ofactuator handle assembly (70), thereby providing a mechanical ground forthe actuating components therein. The proximal end of driver actuator(64) is coupled to a trigger actuation assembly (84) of actuator handleassembly (70), described below. The distal end of driver actuator (64)is coupled to staple driver (24) such that the rotation of trigger (74)longitudinally actuates staple driver (24). As shown in FIGS. 2A-2C,driver actuator (64) comprises a tubular member having an openlongitudinal axis such that actuator (39) coupled to trocar (38) mayactuate longitudinally within and relative to driver actuator (64). Ofcourse it should be understood that other components may be disposedwithin driver actuator (64) as will be apparent to one of ordinary skillin the art in view of the teachings herein.

Shaft assembly (60) may be further constructed in accordance with atleast some of the teachings of U.S. Pat. No. 5,205,459; U.S. Pat. No.5,271,544; U.S. Pat. No. 5,275,322; U.S. Pat. No. 5,285,945; U.S. Pat.No. 5,292,053; U.S. Pat. No. 5,333,773; U.S. Pat. No. 5,350,104; U.S.Pat. No. 5,533,661, the disclosures of which are incorporated byreference herein; and/or in accordance with other configurations as willbe apparent to one of ordinary skill in the art in view of the teachingsherein.

D. Exemplary Actuator Handle Assembly

Referring now to FIGS. 4A-5, actuator handle assembly (70) comprises abody (72), a trigger (74), a lockout feature (82), a trigger actuationassembly (84), and a trocar actuation assembly (90). Trigger (74) of thepresent example is pivotably mounted to body (72) and is coupled totrigger actuation assembly (84) such that rotation of trigger (74) froman unfired position (shown in FIG. 4A) to a fired position (shown inFIG. 4B) actuates driver actuator (64) described above. A spring (78) iscoupled to body (72) and trigger (74) to bias trigger (74) towards theunfired position. Lockout feature (82) is a pivotable member that iscoupled to body (72). In a first, locked position, lockout feature (82)is pivoted upwards and away from body (72) such that lockout feature(82) engages trigger (74) and mechanically resists actuation of trigger(74) by a user. In a second, unlocked position, such as that shown inFIGS. 1 and 4B, lockout feature (82) is pivoted downward such thattrigger (74) may be actuated by the user. Accordingly, with lockoutfeature (82) in the second position, trigger (74) can engage a triggeractuation assembly (84) to fire instrument (10).

As shown in FIGS. 4A-4B, trigger actuation assembly (84) of the presentexample comprises a slidable trigger carriage (86) engaged with aproximal end of driver actuator (64). Carriage (86) includes a set oftabs (88) on a proximal end of carriage (86) to retain and engage a pairof trigger arms (76) extending from trigger (74). Accordingly, whentrigger (74) is pivoted, carriage (86) is actuated longitudinally andtransfers the longitudinal motion to driver actuator (64). In theexample shown, carriage (86) is fixedly coupled to the proximal end ofdriver actuator (64), though this is merely optional. Indeed, in onemerely exemplary alternative, carriage (86) may simply abut driveractuator (64) while a distal spring (not shown) biases driver actuator(64) proximally relative to actuator handle assembly (70).

Trigger actuation assembly (84) may be further constructed in accordancewith at least some of the teachings of U.S. Pat. No. 5,205,459; U.S.Pat. No. 5,271,544; U.S. Pat. No. 5,275,322; U.S. Pat. No. 5,285,945;U.S. Pat. No. 5,292,053; U.S. Pat. No. 5,333,773; U.S. Pat. No.5,350,104; U.S. Pat. No. 5,533,661, the disclosures of which areincorporated by reference herein; and/or in accordance with otherconfigurations as will be apparent to one of ordinary skill in the artin view of the teachings herein.

Body (72) also houses a trocar actuation assembly (90) configured toactuate trocar (38) longitudinally in response to rotation of adjustingknob (98). As best shown in FIGS. 4A-5, trocar actuation assembly (90)of the present example comprises adjusting knob (98), a grooved shank(94), and a sleeve (92). Grooved shank (94) of the present example islocated at a distal end of trocar actuator (39), though it should beunderstood that grooved shank (94) and trocar actuator (39) mayalternatively be separate components that engage to transmitlongitudinal movement. Adjusting knob (98) is rotatably supported by theproximal end of body (72) and is operable to rotate sleeve (92) that isengaged with grooved shank (94) via an internal tab (not shown). Groovedshank (94) of the present example comprises a continuous groove (96)formed in the outer surface of grooved shank (94). Accordingly, whenadjusting knob (98) is rotated, the internal tab rides within groove(96) and grooved shank (94) is longitudinally actuated relative tosleeve (92). Since grooved shank (94) is located at the distal end oftrocar actuator (39), rotating adjusting knob (98) in a first directionadvances trocar actuator (39) distally relative to actuator handleassembly (70). Accordingly, the gap distance d between anvil (40) andstapling head assembly (20) is increased. By rotating adjusting knob(98) in the opposite direction, trocar actuator (39) is actuatedproximally relative to actuator handle assembly (70) to reduce the gapdistance d between anvil (40) and stapling head assembly (20). Thus,trocar actuation assembly (90) is operable to actuate trocar (38) inresponse to rotating adjustment knob (98). Of course otherconfigurations for trocar actuation assembly (90) will be apparent toone of ordinary skill in the art in view of the teachings herein.

Groove (96) of the present example comprises a plurality of differentportions (96A, 96B, 96C) that have a varying pitch or number of groovesper axial distance. The present groove (96) is divided into a distalportion (96A), a middle portion (96B) and a proximal portion (96C). Asshown in FIG. 5, distal portion (96A) comprises a fine pitch or a highnumber of grooves over a short axial distance of grooved shank (94) suchthat a large number of rotations of adjusting knob (98) are required totraverse the short axial distance. Middle portion (96B) comprises asection with comparably coarser pitch or fewer grooves per axialdistance such that relatively few rotations are required to traverse along axial distance. Accordingly, the gap distance d may be quicklyreduced through relatively few rotations of adjusting knob (98).Proximal portion (96C) of the present example is substantially similarto distal portion (96A) and comprises a fine pitch or a high number ofgrooves over a short axial distance of grooved shank (94) such that alarge number of rotations are required to traverse the short axialdistance. Proximal portion (96C) of the present example is positionedwithin sleeve (92) when anvil (40) is substantially near to staplinghead assembly (20) such that indicator bar (110) moves within indicatorwindow (120) along scale (130) to indicate that the anvil gap is withina desired operating range, as will be described in more detail below.Accordingly, when the tab is within proximal portion (96C) of groove(96), each rotation of adjusting knob (98) may reduce the gap distance dby a small amount to provide for fine tuning.

Trocar actuation assembly (90) may be further constructed in accordancewith at least some of the teachings of U.S. Pat. No. 5,205,459; U.S.Pat. No. 5,271,544; U.S. Pat. No. 5,275,322; U.S. Pat. No. 5,285,945;U.S. Pat. No. 5,292,053; U.S. Pat. No. 5,333,773; U.S. Pat. No.5,350,104; U.S. Pat. No. 5,533,661, the disclosures of which areincorporated by reference herein; and/or in accordance with otherconfigurations as will be apparent to one of ordinary skill in the artin view of the teachings herein.

In the example shown in FIGS. 4A-4B, a U-shaped clip (100) is attachedto an intermediate portion of trocar actuator (39) located distally ofgrooved shank (94). U-shaped clip (100) engages with a portion of body(72) to substantially prevent trocar actuator (39) from rotating aboutits axis when adjusting knob (98) is rotated. U-shaped clip (100)further includes an elongated slot (102) on each of its opposite sidesfor receiving an attachment member, such as a screw, bolt, pin, clip,etc., to selectively adjust the longitudinal position of elongated slot(102) of U-shaped clip (100) relative to trocar actuator (39) forpurposes of calibrating indicator bar (110) relative to scale (130).

As shown in FIG. 5, actuator handle assembly (70) further includes anindicator bracket (140) configured to engage and pivot an indicator(104). Indicator bracket (140) of the present example is slidablerelative to body (72) along a pair of slots formed on body (72).Indicator bracket (140) comprises a rectangular plate (144), anindicator arm (146), and an angled flange (142). Angled flange (142) isformed at the proximal end of rectangular plate (144) and includes anaperture (not shown) to slidable mount onto trocar actuator (39) and/orgrooved shank (94). A coil spring (150) is interposed between flange(142) and a boss (152) to bias flange (142) against U-shaped clip (100).Accordingly, when U-shaped clip (100) actuates distally with trocaractuator (39) and/or grooved shank (94), coil spring (150) urgesindicator bracket (140) to travel distally with U-shaped clip (100). Inaddition, U-shaped clip (100) urges indicator bracket (140) proximallyrelative to boss (152) when trocar actuator (39) and/or grooved shank(94) translate proximally, thereby compressing coil spring (150). Ofcourse, it should be understood that in some versions indicator bracket(140) may be fixedly attached to trocar actuator (39) and/or groovedshank (94).

In the present example, a portion of lockout feature (82) abuts asurface (141) of indicator bracket (140) when indicator bracket (140) isin a longitudinal position that does not correspond to when the anvilgap is within a desired operating range (e.g., a green colored region or“green zone”). When the anvil gap is within a desired operating range(e.g., a green colored region or “green zone”), indicator bracket (140)narrows to provide a pair of gaps (145) on either side of an indicatorarm (146) that permits lockout feature (82) to pivot, thereby releasingtrigger (74). Accordingly, lockout feature (82) and indicator bracket(140) can substantially prevent a user from releasing and operatingtrigger (74) until anvil (40) is in a predetermined operating range. Ofcourse it should be understood that lockout feature (82) may be omittedentirely in some versions.

This operating range may be visually communicated to the user via anindicator bar (110) of an indicator (104) shown against a scale (130),described briefly above. At the distal end of indicator bracket (140) isa distally projecting indicator arm (146) which terminates at alaterally projecting finger (148) for controlling the movement ofindicator (104). Indicator arm (146) and finger (148), best shown inFIG. 5, are configured to engage a tab (106) of indicator (104) suchthat indicator (104) is pivoted when indicator bracket (140) is actuatedlongitudinally. In the present example, indicator (104) is pivotablycoupled to body (72) at a first end of indicator (104), though this ismerely optional and other pivot points for indicator (104) will beapparent to one of ordinary skill in the art in view of the teachingsherein. An indicator bar (110) is positioned on the second end ofindicator (104) such that indicator bar (110) moves in response to theactuation of indicator bracket (140). Accordingly, as discussed above,indicator bar (110) is displayed through an indicator window (120)against a scale (130) (shown in FIG. 6) to show the relative gapdistance d between anvil (40) and stapling head assembly (20).

Of course indicator bracket (140), indicator (104), and/or actuatorhandle assembly (70) may be further constructed in accordance with atleast some of the teachings of U.S. Pat. No. 5,205,459; U.S. Pat. No.5,271,544; U.S. Pat. No. 5,275,322; U.S. Pat. No. 5,285,945; U.S. Pat.No. 5,292,053; U.S. Pat. No. 5,333,773; U.S. Pat. No. 5,350,104; U.S.Pat. No. 5,533,661, the disclosures of which are incorporated byreference herein; and/or in accordance with other configurations as willbe apparent to one of ordinary skill in the art in view of the teachingsherein.

II. Exemplary Anvil Tilting Versions

As described above, an anvil such as anvil (40) of FIG. 2A may beinserted into a lumen forming portion of tissue (2), and may beretracted from an anastomosis site being used as described above tostaple portions of tissue (2) to form the anastomosis. For example,FIGS. 7A-9 show upper esophagus (4A) and lower esophagus (4B), which areformed by tissue (2) this is stapled together at an anastomosis (6). Inan esophagectomy, for example, a surgeon may desire to introduce ananvil of a circular stapler trans-orally and in an atraumatic manner.For example, the surgeon may desire to reduce trauma that may occur toan interior surface of the esophagus via trans-oral introduction of theanvil, as well retraction of the anvil, by preventing an outer edge ofthe anvil from interacting with the interior surface of esophagus (4)during insertion and retraction of the anvil. Or the surgeon may wish tointroduce the circular stapler anvil in an atraumatic manner in anintestinal procedure or like procedures as will be apparent to those ofordinary skill in the art in view of the teachings herein. For example,the anvil may be introduced into or retracted from a naturally occurringbody lumen of tissue (2), which may be the intestine, esophagus (4), orsome other portion of the gastrointestinal (GI) tract.

With respect to a trans-oral introduction of the anvil, the anvil may beintroduced trans-orally and directed downward into a patient's esophagus(4) to a first suturing position shown in, for example, FIG. 2A (whereintissue (2) may represent the esophagus). The anvil may then be suturedin the first suturing position as shown in FIG. 2A and as describedabove with respect to anvil (40). The anvil may additionally oralternatively be attached to tissue (2), as shown in FIG. 2A in anysuitable manner as will be apparent to those of ordinary skill in theart in view of the teachings herein. Stapling head assembly (20) may beintroduced via, for example, an abdominal opening and led up esophagus(4) to a second suturing position disposed below the first suturingposition. Stapling head assembly (20) may then be sutured to tissue (2)as described above or attached in any suitable manner as will beapparent to those of ordinary skill in the art in view of the teachingsherein. Anvil (40) and stapling head assembly (20) are then operable tointeract to sever and staple tissue (2) as described above to createanastomosis (6) (created by two reconnected portions of tissue (2)) asshown in FIGS. 7A-9, which are described in greater detail furtherbelow.

Additional exemplary modifications that may be provided for instrument(10) to reduce esophageal trauma during transport of anvil (40) will bedescribed in greater detail below. Various suitable ways in which thebelow teachings may be incorporated into instrument (10) will beapparent to those of ordinary skill in the art. Similarly, varioussuitable ways in which the below teachings may be combined with variousteachings of the references cited herein will be apparent to those ofskill in the art. It should also be understood that the below teachingsare not limited to instrument (10) or devices taught in the referencescited herein. The below teachings may be readily applied to variousother kinds of instruments, including instruments that would not beclassified as surgical staplers. Various other suitable devices andsettings in which the below teachings may be applied will be apparent tothose of ordinary skill in the art in view of the teachings herein.

A. Exemplary First Tilting Anvil Version Including Multiple Pivots

As shown in FIGS. 7A-7C, an exemplary first tilting anvil (240) includesanvil head (248) and a proximal shaft (242) extending proximally fromanvil head (248). Proximal shaft (242) is attachable to trocar (38) in amanner as described above with respect to proximal shaft (42) or as willbe apparent to one of ordinary skill in the art in view of the teachingsherein. Proximal shaft (242) comprises a flexible material, a rigidmaterial, or any suitable material as will be apparent to one ofordinary skill in the art in view of the teachings herein. Anvil head(248) is similar to anvil head (48), described above, and includes aplurality of staple forming pockets (not shown) formed in a proximalface (250) of anvil head (248). Anvil head (248) operates with staples(66) in a similar manner as described above for anvil head (48).

Anvil head (248) is linked to proximal shaft (242). Proximal shaft (242)includes link (254) and shaft portion (256). Link (254) and shaftportion (256) are linked together via linking pivot (258). Link (254) isrotatable about a longitudinal axis of linking pivot (258). Anvil head(248) is linked to link (254) via head pivot (252). Anvil head (248) isrotatable about a longitudinal axis of head pivot (252) in the directionof arrow (A), as shown in FIG. 7B. Link (254) of proximal shaft (242) isrotatable about linking pivot (258) in the direction of arrow (B), asshown in FIG. 7C. Head pivot (252), and other pivots of the presentdisclosure, may be comprised of, for example, pins received throughchannels or other suitable structures as will be apparent to those ofordinary skill in the art in view of the teachings herein.

As shown in FIG. 7B, driver rod (253) is disposed and translatablewithin proximal shaft (242). When driver rod (253) is advanced to adistal position, driver rod (253) engages an off-center point ofproximal face (250) of anvil (240) with sufficient force to tilt anvilhead (248) about head pivot (252) in the direction of arrow (A). Driverrod (253) keeps anvil head (248) in the tilted position while driver rod(253) is in the distal position. In some versions, driver rod (253) isretracted proximally before link (254) rotates about linking pivot (258)as shown in FIG. 7C. In some other versions, driver rod (253) stays inthe distal position when link (254) rotates about linking pivot (258).It should therefore be understood that driver rod (253) may eitherproximally terminate distal to linking pivot (258); or driver rod mayflex through linking pivot (258).

In some versions, the longitudinal position of driver rod (253) relativeto anvil head (248) is based on the position of anvil (240) in relationto stapling head assembly (20). For instance, driver rod (253) may beconfigured to remain in the distal position whenever anvil (240) isdecoupled from trocar (38) of stapling head assembly (20). In some suchversions, driver rod (253) may automatically retract proximally uponcoupling anvil (240) with trocar (38). Alternatively, driver rod (253)may be configured to remain in the distal position even after anvil(240) is coupled with trocar (38), when anvil (240) is still spacedsignificantly from stapling head assembly (20) (e.g., before anvil (240)is drawn toward stapling head assembly (20) by trocar (38) to clamptissue between anvil (240) and stapling head assembly (20), etc.). Insome such versions, a feature in anvil (240) and/or a feature instapling head assembly (20) may be configured to retract driver rod(253) proximally, thereby allowing anvil head (248) to pivot to theposition shown in FIG. 7A, when anvil (240) is retracted within acertain distance relative to stapling head assembly (20). For instance,a camming feature of proximal shaft (242) may interact with acomplementary feature of stapling head assembly (20) when proximal shaft(242) is retracted to a certain position within stapling head assembly(20). Instead of automating the retraction of driver rod (253), aseparate actuator may extend along shaft assembly (60) to actuatorhandle assembly (70), enabling the operator to selectivelyadvance/retract driver rod (253) independently. As still anothervariation, driver rod (253) may be integral with shaft portion (256),and the combination of driver rod (253) and shaft portion (256) mayselectively slide relative to link (254) and pivot (258) to selectivelyadvance/retract driver rod (253). As yet another merely illustrativeexample, an electromechanical feature (e.g., solenoid, etc.) may be usedto selectively advance/retract driver rod (253) in an automated fashionor in a manual/independent fashion. Other suitable ways in which driverrod (253) may be actuated will be apparent to those of ordinary skill inthe art in view of the teachings herein.

In use, anvil (240) is inserted into an interior lumen of tissue (2) inan anvil inserting direction. For instance, anvil (240) may be insertedtrans-orally into esophagus (4) of a patient. Before anvil (240) isinserted, a portion of esophagus (4) may be resected and removed (e.g.,using an endocutter type of linear cutting/stapling device), resultingin separation of upper esophagus (4A) from lower esophagus (4B). Anvil(240) may be fed down upper esophagus (4A) until it reaches the bottomend of upper esophagus (4A), where instrument (10) may be used to joinupper esophagus (4A) and lower esophagus (4B) through an end-to-endanastomosis (6). Anvil (240) may be in positions shown in FIG. 7B or 7Cwhile being inserted, for example, and prior to shaft portion (256)being secured to a trocar of a stapling head assembly, such as in themanner described above to attach anvil (40) to trocar (38) and staplinghead assembly (20). In some versions, conventional surgical graspers areinserted through esophagus (4) to grasp shaft portion (256) and therebypull anvil (240) to the anastomosis site via upper esophagus (4A).

Anvil (240) may be straightened into a position as shown in FIG. 7Aprior to interacting with stapling head assembly (20) as describedabove. Stapling head assembly (20) is advanced toward anvil (240)through lower esophagus (4B) in a stapling direction that is oppositethe anvil inserting direction. Shaft portion (256) is then coupled withtrocar (38). The force deployed by the firing and stapling system asdescribed above may straighten anvil (240) and shaft portion (256) intothe position shown in FIG. 7A (for example, when instrument (10) clampstissue between stapling head assembly (20) and anvil head (248)). Thepositions will be described further below with respect to a retractionof anvil (240). Anvil (240) may then be used as described above tostaple tissue (2) with staples (66). FIG. 7A shows a position afterwhich anvil (240) has been used to staple tissue (2) with staples (66),and after which knife (36) has severed tissue, thereby creating a secureanastomosis (6).

To retract anvil (240), driver rod (253) is distally advanced, causinganvil head (248) to pivot about head pivot (252) in the direction ofarrow (A) shown in FIG. 7B. Remaining in an extended position, driverrod (253) assists to maintain anvil head (248) in the first flipped ortilted position shown in FIG. 7B in a manner as will be apparent tothose of ordinary skill in the art in view of the teachings herein. Forexample, driver rod (253) may contain a laterally offset portion (notshown) that abuts against proximal face (250) when driver rod (253) isin the extended position. The laterally offset portion thus preventsanvil head (248) from rotating back to the position of anvil head (248)shown in FIG. 7A.

Shaft portion (256) is proximally retracted along the direction of arrow(C) to retract anvil (240) through the lumen defined by tissue (2) (suchas the esophagus (4))). Load on anvil head (248) from this retractionmay provide the pivoting at linking pivot (258). For example, anvil head(248) may abut inner surface walls of tissue (2), causing link (254) topivot about linking pivot (258) at angles of from about 30 degrees toabout 45 degrees with respect to shaft portion (256) as anvil (240) isretracted proximally. Further, anvil head (248) is pivoted about headpivot (252) such that anvil head (248) may be retracted within aninternal passageway of tissue (2) with minimal interaction with theinner surface walls of tissue (2). In other words, the above-describedtilting and pivoting may prevent the outer edge of anvil head (248) fromscraping against the inner wall of esophagus as anvil (240) istransported through esophagus. In the position shown in FIG. 7C, forexample, link (254) is tilted with respect to shaft portion (256) andanvil head (248) is tilted with respect to link (254) into a retractionposition. A plane of anvil head (248) depicted as plane (PP) in FIG. 7Cdefines an acute angle with longitudinal axis (LLA) of shaft portion(256) of proximal shaft (242), with vertex (VV) of the angle beingpositioned lower than head pivot (252). In the retraction position, aretraction of anvil (240) in the direction of arrow (C) substantiallyavoids snagging a lowermost portion of anvil head (248), disposedclosest to linking pivot (258), with an interior surface of tissue (2),and particularly with edges of anastomosis (6) that are shown as stapledtogether via staples (66).

Driver rod (253) may remain extended during retraction of anvil (240) asdescribed above. Further, anvil head (248) may be lockable at either theposition shown in FIG. 7B or the position shown in FIG. 7C to easeextraction of anvil head (248) from anastomosis (6) to reduceanastomosis trauma during the retraction of anvil (240). For example, aninternal projection in link (254) may be received in an internal notchin shaft portion (256) laterally offset from linking pivot (258) anddisposed at a location to lock link (254) at a desired tilting anglewith respect to shaft portion (256). By way of example only, shaftportion (256) may selectively slide relative to link (254) and pivot(258) to selectively lock the tilted angle of link (254) at pivot (258).

In some versions, anvil head (248) is resiliently biased to tilt to theposition shown in FIGS. 7B and 7C. In such versions, driver rod (253)may be omitted (or still be included). In addition or in thealternative, link (254) may be resiliently biased to tilt to theposition shown in FIG. 7C. Various suitable ways in which such biasesmay be provided will be apparent to those of ordinary skill in the artin view of the teachings herein. It should also be understood that, insuch versions, link (254) and anvil head (248) may eventually tilt tothe positions shown in FIG. 7A once anvil (240) is coupled with trocar(38) and anvil (240) is retracted toward stapling head assembly (20). Inother words, the internal axial passageway within stapling head assembly(20) may straighten link (254) and the distal face of stapling headassembly (20) may straighten anvil head (248).

Other suitable ways in which an anvil may include a multi-pivot shaftwill be apparent to those of ordinary skill in the art in view of theteachings herein.

B. Exemplary Second Tilting Anvil Version Including Off-Center Pivot

FIGS. 8-9 show an exemplary second tilting anvil (340) including anvilhead (348) and a proximal shaft (342) extending proximally from anvilhead (348). Proximal shaft (342) is attachable to trocar (38) in amanner as described above with respect to proximal shaft (42) or as willbe apparent to one of ordinary skill in the art in view of the teachingsherein. Proximal shaft (342) comprises a flexible material, a rigidmaterial, or any suitable material as will be apparent to one ofordinary skill in the art in view of the teachings herein. Anvil head(348) is similar to anvil head (48), described above, and includes aplurality of staple forming pockets (not shown) formed in a proximalface (350) of anvil head (348). Anvil head (348) operates with staples(66) in a similar manner as described above for anvil head (48).

Anvil head (348) includes linking connector (351), which connects anvilhead (348) to proximal shaft (342). Anvil head (348) is linked toproximal shaft (342) via off-set head pivot (352). Anvil head (348) isrotatable about a longitudinal axis of head pivot (352) in the directionof arrow (D), as shown in FIG. 9. Driver rod (353) is disposed andtranslatable within proximal shaft (342) in a manner similar to thatdescribed for driver rod (253). Proximal shaft (342) includes a firstportion (354) in which driver rod (353) is disposed and a second portion(356) extending laterally from a distal end of first portion (354) ofproximal shaft (342). Head pivot (352) is disposed in second portion(356) and is off-set from the longitudinal axis of first portion (354).Head pivot (352) connects linking connector (351) of anvil head (348) tosecond portion (356) of proximal shaft (342), such that linkingconnector (351) and anvil head (348) are rotatable relative to secondportion (356) about a longitudinal axis of head pivot (352).

In use, anvil (340) is inserted into an interior lumen of tissue (2)(e.g., upper esophagus (4A), etc.) in an anvil inserting direction in amanner similar to that described above for anvil (240). Anvil (340) maybe in a position shown in FIG. 9 while being inserted, for example. Whenproximal shaft (342) is coupled with trocar (38), the clamping of tissuebetween stapling head assembly (20) and anvil (340) will straightenanvil (340) before a firing actuation as described above. Thus, theforce deployed by the firing and stapling system as described above willstraighten anvil (340) into the position shown in FIG. 8. Anvil (340)may then be used as described above to staple interior surfaces oftissue (2). FIG. 8 shows a position after which anvil (340) has beenused to staple interior surfaces of a lumen of tissue (2) with staples(66) to create anastomosis (6).

To retract anvil (340), driver rod (353) is distally advanced, causinganvil head (348) to pivot about head pivot (352) in the direction ofarrow (D) shown in FIG. 9. Driver rod (353) may remain advanced toassist in maintaining anvil head (248) in the tilted position shown inFIG. 9. Because second portion (356) is laterally off-set from firstportion (354), anvil head (348) is able to rotate about head pivot (352)into a position in which anvil head (348) is at an obtuse angle withrespect to a starting position of anvil head (348). In particular, anvilhead (348) rotates more than 90 degrees with respect to proximal shaft(342) in the present example. A plane of anvil head (348) depicted asplane (P) in FIG. 9 defines an acute angle with longitudinal axis (LA)of proximal shaft (342), with the vertex (V) of the angle being at aposition that is lower than head pivot (352). Thus, once flipped, aproximal end of anvil head (348) is disposed below second portion (356)and between ends of second portion (356) and first portion (354) ofproximal shaft (342).

Anvil head (348) may be lockable at the obliquely angled position ofFIG. 9 to ease extraction of anvil head (348) from anastomosis (6) in amanner similar to that described above to lock anvil head (248) as willbe apparent to those of ordinary skill in the art in view of theteachings herein. For example, a projection on an interior surface oflinking connector (351) may advance until receipt in a complementarynotch disposed in an interior surface of second portion (356).Additionally or alternatively, a laterally projecting portion of driverod (353) may be received into a notch disposed in an underside oflinking connector (351). Other suitable ways in which drive rod (353)may be selectively locked in the distal position shown in FIG. 9 (or atleast resiliently biased to the distal position shown in FIG. 9) will beapparent to those of ordinary skill in the art in view of the teachingsherein.

First portion (354) is proximally retracted downwardly through esophagus(4) to retract anvil (340) from esophagus (4) in a manner as describedabove. Load on anvil head (348) from this retraction may cause proximalshaft (342) to tilt in a direction opposite arrow (D) while withinesophagus (4), such that longitudinal axis (LA) of proximal shaft (342)is tilted relative to the axis of esophagus (4). With anvil head (348)and proximal shaft (342) tilted (as shown in FIG. 9), anvil head (348)may be retracted downwardly esophagus (4) with minimal interactionbetween the outer edge of anvil head (348) and the inner surface wallsof esophagus (4). In other words, the above-described tilting andpivoting may prevent the outer edge of anvil head (348) from scrapingagainst the inner wall of esophagus as anvil (340) is transportedthrough esophagus.

III. Miscellaneous

It should be understood that any one or more of the teachings,expressions, embodiments, examples, etc. described herein may becombined with any one or more of the other teachings, expressions,embodiments, examples, etc. that are described herein. Theabove-described teachings, expressions, embodiments, examples, etc.should therefore not be viewed in isolation relative to each other.Various suitable ways in which the teachings herein may be combined willbe readily apparent to those of ordinary skill in the art in view of theteachings herein. Such modifications and variations are intended to beincluded within the scope of the claims.

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference. Any material, or portion thereof, thatis said to be incorporated by reference herein, but which conflicts withexisting definitions, statements, or other disclosure material set forthherein will only be incorporated to the extent that no conflict arisesbetween that incorporated material and the existing disclosure material.

Versions of the devices described above may have application inconventional medical treatments and procedures conducted by a medicalprofessional, as well as application in robotic-assisted medicaltreatments and procedures. By way of example only, various teachingsherein may be readily incorporated into a robotic surgical system suchas the DAVINCI™ system by Intuitive Surgical, Inc., of Sunnyvale, Calif.Similarly, those of ordinary skill in the art will recognize thatvarious teachings herein may be readily combined with various teachingsof U.S. Pat. No. 6,783,524, entitled “Robotic Surgical Tool withUltrasound Cauterizing and Cutting Instrument,” published Aug. 31, 2004,the disclosure of which is incorporated by reference herein.

Versions described above may be designed to be disposed of after asingle use, or they can be designed to be used multiple times. Versionsmay, in either or both cases, be reconditioned for reuse after at leastone use. Reconditioning may include any combination of the steps ofdisassembly of the device, followed by cleaning or replacement ofparticular pieces, and subsequent reassembly. In particular, someversions of the device may be disassembled, and any number of theparticular pieces or parts of the device may be selectively replaced orremoved in any combination. Upon cleaning and/or replacement ofparticular parts, some versions of the device may be reassembled forsubsequent use either at a reconditioning facility, or by a userimmediately prior to a procedure. Those skilled in the art willappreciate that reconditioning of a device may utilize a variety oftechniques for disassembly, cleaning/replacement, and reassembly. Use ofsuch techniques, and the resulting reconditioned device, are all withinthe scope of the present application.

By way of example only, versions described herein may be sterilizedbefore and/or after a procedure. In one sterilization technique, thedevice is placed in a closed and sealed container, such as a plastic orTYVEK bag. The container and device may then be placed in a field ofradiation that can penetrate the container, such as gamma radiation,x-rays, or high-energy electrons. The radiation may kill bacteria on thedevice and in the container. The sterilized device may then be stored inthe sterile container for later use. A device may also be sterilizedusing any other technique known in the art, including but not limited tobeta or gamma radiation, ethylene oxide, or steam.

Having shown and described various embodiments of the present invention,further adaptations of the methods and systems described herein may beaccomplished by appropriate modifications by one of ordinary skill inthe art without departing from the scope of the present invention.Several of such potential modifications have been mentioned, and otherswill be apparent to those skilled in the art. For instance, theexamples, embodiments, geometrics, materials, dimensions, ratios, steps,and the like discussed above are illustrative and are not required.Accordingly, the scope of the present invention should be considered interms of the following claims and is understood not to be limited to thedetails of structure and operation shown and described in thespecification and drawings.

1-20. (canceled)
 21. A circular stapler apparatus for stapling tissue,comprising: (a) a stapling head assembly; and (b) an anvil configured toform staples advanced by the stapling head assembly, the anvilcomprising: (i) an anvil head having a proximal face, (ii) a shaftextending along a longitudinal shaft axis between a distal shaft endthat couples to the anvil head and a proximal shaft end that freelyterminates, and (iii) a pivot defining a pivot axis; wherein the anvilhead is configured to pivot about the pivot axis between a firstposition and a tilted second position, wherein in the first position theproximal face of the anvil head extends perpendicularly to the shaftaxis, and in the tilted second position the proximal face extendsobliquely to the shaft axis to define a distally opening acute anglewith the shaft axis, wherein a vertex of the acute angle is locatedproximally of the pivot.
 22. The circular stapler apparatus of claim 21,wherein the vertex of the acute angle is located distally of theproximal shaft end.
 23. The circular stapler apparatus of claim 21,wherein the anvil head further includes a proximally extending connectorthat pivotably couples the anvil head to the distal shaft end.
 24. Thecircular stapler apparatus of claim 21, further comprising a drivermember configured to urge the anvil head toward the tilted secondposition.
 25. The circular stapler apparatus of claim 24, wherein thedriver member is arranged within the shaft.
 26. The circular staplerapparatus of claim 25, wherein the driver member is movable between aretracted position in which the driver rod permits the anvil head tomove to the first position, and a deployed position in which the drivermember urges the anvil head toward the tilted second position.
 27. Thecircular stapler apparatus of claim 26, wherein the driver member isarranged to directly contact the proximal face of the anvil head whenthe driver member is in the deployed position.
 28. The circular staplerapparatus of claim 24, wherein the driver member includes a rod thatextends coaxially with the shaft axis.
 29. The circular staplerapparatus of claim 21, wherein the shaft includes a first shaft portionand a second shaft portion coupled to the first shaft portion, whereinthe first shaft portion is pivotably coupled to the anvil head with thepivot to provide the anvil head with a first degree of movement relativeto the shaft axis, and the first shaft portion is movable relative tothe second shaft portion to provide the anvil head with a second degreeof movement relative to the shaft axis.
 30. The circular staplerapparatus of claim 29, wherein the anvil further comprises a secondpivot that couples the first shaft portion to the second shaft portion,wherein the second pivot is located proximally of the pivot and isconfigured to enable the first shaft portion to pivot relative to secondshaft portion.
 31. The circular stapler apparatus of claim 30, whereinthe first and second shaft portions are configured to align coaxiallywhen the anvil head is in the first position such that the pivot, thesecond pivot, and the proximal shaft end are arranged collinearly. 32.The circular stapler apparatus of claim 30, wherein the anvil head isconfigured to pivot about the first pivot axis relative to the firstshaft portion in a first pivoting direction, and the first shaft portionis configured to pivot about the second pivot axis relative to thesecond shaft portion in a second pivoting direction that is opposite thefirst pivoting direction.
 33. The circular stapler apparatus of claim21, wherein the shaft includes a first shaft portion extending along theshaft axis and a second shaft portion rigidly coupled to the first shaftportion and extending away from the shaft axis, wherein the pivot isarranged on the second shaft portion and is laterally offset from theshaft axis.
 34. The circular stapler apparatus of claim 21, wherein theshaft includes a laterally extending distal shaft portion configured toconfront the proximal face of the anvil head when the anvil head is inthe first position.
 35. The circular stapler apparatus of claim 21,wherein the pivot couples the anvil head to the shaft at a locationoffset from a central axis of the anvil head.
 36. A circular staplerapparatus for stapling tissue, comprising: (a) a stapling head assembly;and (b) an anvil configured to form staples advanced by the staplinghead assembly, the anvil comprising: (i) an anvil head having a proximalface, (ii) a shaft extending proximally from the anvil head, and (iii) apivot coupling the anvil head to the shaft and defining a pivot axis;wherein the anvil head is configured to pivot about the pivot axisbetween a first position and a tilted second position, wherein in thefirst position the proximal face of the anvil head extends along animaginary plane oriented perpendicular to the shaft axis, wherein in thetilted second position the proximal face forms a distally opening obtuseangle with the imaginary plane.
 37. The circular stapler apparatus ofclaim 36, wherein the shaft includes a proximal shaft portion and adistal shaft portion rigidly coupled to the proximal shaft portion,wherein the proximal shaft portion extends along the shaft axis and thedistal shaft portion extends away from the shaft axis.
 38. The circularstapler apparatus of claim 36, wherein the pivot is laterally offsetfrom the shaft axis.
 39. A circular stapler apparatus for staplingtissue, comprising: (a) a stapling head assembly; and (b) an anvilconfigured to form staples advanced by the stapling head assembly, theanvil comprising: (i) an anvil head, (ii) a shaft extending proximallyfrom the anvil head and having a first shaft portion and a second shaftportion, (iii) a first pivot coupling the anvil head to the first shaftportion and defining a first pivot axis, and (iv) a second pivotcoupling the first shaft portion to the second shaft portion anddefining a second pivot axis; wherein the anvil head is configured topivot about the first pivot axis in a first pivot direction, and thefirst shaft portion is configured to pivot about the second pivot axisin a second pivot direction different than the first pivot direction.40. The circular stapler apparatus of claim 39, wherein the first andsecond pivots are arranged along a longitudinal axis that extendsparallel to a longitudinal axis defined by the first shaft portion.